Models 20, 20-A and 21 

• Schematic and Parts list (Beitman's Volume 1)

37-630  ( From Rider's 7-57 to 7-60) 

• Schematic
• Alignment
• Electrical Specifications
• Under chassis view, Parts List

• Schematic
• Alignment
• Notes, voltage, socket and transformer data
• Parts location and parts list.

40-180, 40-185, 40-190 

• Schematic

• Schematic
• Alignment and adjustment

• Specifications, Circuit Description and Troubleshooting
• Calibrating dial backplate, Troubleshooting within Section 1
• Troubleshooting within Section 2
• Troubleshooting within Section 3
• Troubleshooting within Section 4
• Alignment Procedure
• Schematic
• Replacement parts list

• Page 1 - Schematic
• Page 2 - Chassis Layout and Alignment
• Page 3 - Dial cord diagram and Voltage and resistance chart

• Schematic

• Specifications, Circuit Description, Troubleshooting
• Troubleshooting continued
• Troubleshooting continued
• Schematic, part 1
• Schematic, part 2
• Alignment, part 1 and dial calibration
• Alignment, part 2 and dial cord installation
• Parts List
• Differences for Model 48-1262 (Code 122)

• Schematic part 1
• Schematic part 2
• Schematic part 3

48-1283 Similar to 48-1262 with the following differences: 

• Page 1
• Page 2

50-1718 

• Specifications and Dial Drive-cord Installation
• Parts list and Parts placement (under Chassis)
• Schematic Diagram
• Alignment procedure and Top of chassis parts and trimmer locations

• Schematic

• Schematic
• Parts List

• Schematic and Dial Stringing
• Alignment

M-1741 Radio-Phonograph 

• Schematic Page 1
• Schematic Page 2